ADSC 2010 Exam 3 Study Guide Section 3 Lectures Diseases Disease an abnormal pathological condition that affects parts or all of an organism o Acute disease a sudden onset of clinical signs and short duration of illness o Chronic disease develop over a period of time and can be treated but not necessarily cured Etiology the study of the cause of disease Pathology the study and diagnosis of a disease along with the tissues and organs associated with it Natural defense system o Resistance antibodies acidic environment in stomach etc o Immune system o Behavioral adaptations o Genetics Cause of diseases o Parasites o Bacterial infections o Pathogens Infectious diseases diseases caused by living organisms Four steps for vitality of infectious diseases o Pathogen must enter its host o Must adapt and multiply inside the host s body o Exit the host o Infect another host to start the cycle over again Zoonotic disease a disease that can be passed between animals and humans o 60 of infectious diseases in humans o Causes Contact with saliva blood urine or feces of an infected animal Being bitten by a tick or mosquito vector inject DNA into cells Eating or drinking something unsafe unpasteurized milk undercooked meat unwashed fruits and vegetables o Examples Malaria E Coli West Nile Anthrax Epidemiology the study of patterns causes and effects of health and disease conditions within a population What defines a population o Location o Breed o Use Epidemiologic Triad o Agent Factors Virulence strength of virus Infectivity Toxicity Environmental hardiness o Host Factors How susceptible host is Intrinsic can t change age gender genetics Extrinsic can change previous exposure reproductive status o Environmental Factors Housing Environmental Conditions Nutrition Iceberg Concept observation in most cases that only a small amount of information is available because most of the data is hidden o Clinical diseases show observable symptoms that can be used to diagnose a disease o Subclinical diseases no recognizable clinical symptoms due to disease being in earliest stages or so mild it is only diagnosed with special tests How diseases are spread o Direct contact o Airborne organisms o Introducing an animal carrying the subclinical disease into the herd o Contact with contaminated objects o Can be spread through vectors o Contaminated premises Cattle Common Diseases o Blackleg highly fatal bacterial infection in young cattle Inflammation throughout body and fever Can be prevented by vaccines o Scours diarrhea caused by bacteria viruses or parasites Occurs in younger cows Important to catch early due to dehydration o Pink eye contagious bacterial infection in eye Starts with outer eye then goes to eyeball if not treated Can lead to blindness Horse Common Diseases o Cushings Syndrome excessive secretion of cortisol due to pituitary gland tumor Weight loss abnormal hair coat and ulcers Chronic can t be treated o Strangles very contagious bacterial infection affecting lymphoid tissue of upper respiratory tract Can be prevented by vaccines Treated by lysing abscesses and with antibiotics o Equine infectious anemia EIA regenerative disease similar to human AIDS Spread by biting insects Coggins test required to prove your horse is tested negative within the last year Weight loss depression fever results in euthanasia Swine Common Diseases o Glassers disease caused by bacterium and affects younger pigs Fatigued refuse to eat o Porcine parvovirus different from parvo in dogs Resistant to many disinfectants contracted easily Deformed or mummified fetuses Sheep Common Diseases o Barber pole worm internal parasite entering sheep by ingestion Weight loss diarrhea weakness and can lead to death Deworming schedule to prevent o Mastitis bacterial infection of mammary gland Heavy milkers more prone Swelling and discoloration Animal Health Directional Terms on Animal o Cranial towards head o Caudal towards tail o Ventral towards underside o Dorsal along the back The Work Up o History medicines origins o Clinical examinations TPR o Palpation exterior interior o Specimen collection blood urine milk feces o Necropsy Differential Diagnosis given a symptom that could be associated with many diseases Basic Vitals will be given a number in one of the following categories and will be asked is this in range Species Temperature Resting Heart Rate Respiratory Rate Cow 98 102 5 48 89 26 50 Horse 99 1 100 8 28 40 10 14 Goat 101 3 101 5 70 80 12 15 Pig 101 6 103 6 70 120 32 58 Sheep 100 9 103 8 70 80 16 34 Immune System Roles o Prevent entry of infectious agents Surface barriers skin mucous membranes digestive and lung linings o Attack those that have gained entry Innate Immunity nonspecific immune responses that acts quickly but has a short duration to buy body some time Adaptive Immunity more specific vital form used to recognize cause of issue and secrete specific things to fight longer duration o Antibodies proteins produced in body to attack infectious agents and neutralized them produced in spleen and bone marrow Bind to antigen either to neutralize them or mark them for destruction by innate immune system o Passive Immunity antibodies through placenta colostrum or blood handed o Active Immunity body has to stimulate antibody production by either having the disease and recovering from it or being vaccinated Antigen a toxin or foreign substance that induces an immune response T Cell produced in thymus o Can be cytotoxic can kill without use of antibodies o Helps B cells secrete antibodies o Memory of pathogen to increase effectiveness and speed next time B Cell produced in bone marrow o Produce antibodies o Memory of pathogen Animal Criteria for Maintenance o Acceptable Health use nutrients properly immune system capable of mounting a response o Proper Nutrition support immune system with enough energy to fuel immune cell production enough protein for the structure of cells and antibodies and enough vitamins minerals o Under no low stress temperatures weaning handling transportation Short term stress innate immune system Closed Herd extreme doesn t intake any animals Open Herd all in or all out for example Vaccination exposure to an antigen in hopes of stimulating an immune response o Not 100 prevention o Goal active immunity o Modified live symptoms may occur o Killed safer easier to handle not a big immune response usually needs booster Health Issues not Disease Related o Housing Stress Animal Factors Q Fever bacterial